user/sven/linux.git/kernel/trace, branch v4.9.119

ring_buffer: tracing: Inherit the tracing setting to next ring buffer

2018-08-09T10:17:59Z

commit 73c8d8945505acdcbae137c2e00a1232e0be709f upstream. Maintain the tracing on/off setting of the ring_buffer when switching to the trace buffer snapshot. Taking a snapshot is done by swapping the backup ring buffer (max_tr_buffer). But since the tracing on/off setting is defined by the ring buffer, when swapping it, the tracing on/off setting can also be changed. This causes a strange result like below: /sys/kernel/debug/tracing # cat tracing_on 1 /sys/kernel/debug/tracing # echo 0 > tracing_on /sys/kernel/debug/tracing # cat tracing_on 0 /sys/kernel/debug/tracing # echo 1 > snapshot /sys/kernel/debug/tracing # cat tracing_on 1 /sys/kernel/debug/tracing # echo 1 > snapshot /sys/kernel/debug/tracing # cat tracing_on 0 We don't touch tracing_on, but snapshot changes tracing_on setting each time. This is an anomaly, because user doesn't know that each "ring_buffer" stores its own tracing-enable state and the snapshot is done by swapping ring buffers. Link: http://lkml.kernel.org/r/153149929558.11274.11730609978254724394.stgit@devbox Cc: Ingo Molnar Cc: Shuah Khan Cc: Tom Zanussi Cc: Hiraku Toyooka Cc: stable@vger.kernel.org Fixes: debdd57f5145 ("tracing: Make a snapshot feature available from userspace") Signed-off-by: Masami Hiramatsu [ Updated commit log and comment in the code ] Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Sudip Mukherjee Signed-off-by: Greg Kroah-Hartman

tracing: Quiet gcc warning about maybe unused link variable

2018-08-03T05:55:12Z

commit 2519c1bbe38d7acacc9aacba303ca6f97482ed53 upstream. Commit 57ea2a34adf4 ("tracing/kprobes: Fix trace_probe flags on enable_trace_kprobe() failure") added an if statement that depends on another if statement that gcc doesn't see will initialize the "link" variable and gives the warning: "warning: 'link' may be used uninitialized in this function" It is really a false positive, but to quiet the warning, and also to make sure that it never actually is used uninitialized, initialize the "link" variable to NULL and add an if (!WARN_ON_ONCE(!link)) where the compiler thinks it could be used uninitialized. Cc: stable@vger.kernel.org Fixes: 57ea2a34adf4 ("tracing/kprobes: Fix trace_probe flags on enable_trace_kprobe() failure") Reported-by: kbuild test robot Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Greg Kroah-Hartman

tracing/kprobes: Fix trace_probe flags on enable_trace_kprobe() failure

2018-08-03T05:55:12Z

commit 57ea2a34adf40f3a6e88409aafcf803b8945619a upstream. If enable_trace_kprobe fails to enable the probe in enable_k(ret)probe it returns an error, but does not unset the tp flags it set previously. This results in a probe being considered enabled and failures like being unable to remove the probe through kprobe_events file since probes_open() expects every probe to be disabled. Link: http://lkml.kernel.org/r/20180725102826.8300-1-asavkov@redhat.com Link: http://lkml.kernel.org/r/20180725142038.4765-1-asavkov@redhat.com Cc: Ingo Molnar Cc: stable@vger.kernel.org Fixes: 41a7dd420c57 ("tracing/kprobes: Support ftrace_event_file base multibuffer") Acked-by: Masami Hiramatsu Reviewed-by: Josh Poimboeuf Signed-off-by: Artem Savkov Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Greg Kroah-Hartman

tracing: Fix possible double free in event_enable_trigger_func()

2018-08-03T05:55:12Z

commit 15cc78644d0075e76d59476a4467e7143860f660 upstream. There was a case that triggered a double free in event_trigger_callback() due to the called reg() function freeing the trigger_data and then it getting freed again by the error return by the caller. The solution there was to up the trigger_data ref count. Code inspection found that event_enable_trigger_func() has the same issue, but is not as easy to trigger (requires harder to trigger failures). It needs to be solved slightly different as it needs more to clean up when the reg() function fails. Link: http://lkml.kernel.org/r/20180725124008.7008e586@gandalf.local.home Cc: stable@vger.kernel.org Fixes: 7862ad1846e99 ("tracing: Add 'enable_event' and 'disable_event' event trigger commands") Reivewed-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Greg Kroah-Hartman

tracing: Fix double free of event_trigger_data

2018-08-03T05:55:12Z

commit 1863c387259b629e4ebfb255495f67cd06aa229b upstream. Running the following: # cd /sys/kernel/debug/tracing # echo 500000 > buffer_size_kb [ Or some other number that takes up most of memory ] # echo snapshot > events/sched/sched_switch/trigger Triggers the following bug: ------------[ cut here ]------------ kernel BUG at mm/slub.c:296! invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC PTI CPU: 6 PID: 6878 Comm: bash Not tainted 4.18.0-rc6-test+ #1066 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016 RIP: 0010:kfree+0x16c/0x180 Code: 05 41 0f b6 72 51 5b 5d 41 5c 4c 89 d7 e9 ac b3 f8 ff 48 89 d9 48 89 da 41 b8 01 00 00 00 5b 5d 41 5c 4c 89 d6 e9 f4 f3 ff ff <0f> 0b 0f 0b 48 8b 3d d9 d8 f9 00 e9 c1 fe ff ff 0f 1f 40 00 0f 1f RSP: 0018:ffffb654436d3d88 EFLAGS: 00010246 RAX: ffff91a9d50f3d80 RBX: ffff91a9d50f3d80 RCX: ffff91a9d50f3d80 RDX: 00000000000006a4 RSI: ffff91a9de5a60e0 RDI: ffff91a9d9803500 RBP: ffffffff8d267c80 R08: 00000000000260e0 R09: ffffffff8c1a56be R10: fffff0d404543cc0 R11: 0000000000000389 R12: ffffffff8c1a56be R13: ffff91a9d9930e18 R14: ffff91a98c0c2890 R15: ffffffff8d267d00 FS: 00007f363ea64700(0000) GS:ffff91a9de580000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055c1cacc8e10 CR3: 00000000d9b46003 CR4: 00000000001606e0 Call Trace: event_trigger_callback+0xee/0x1d0 event_trigger_write+0xfc/0x1a0 __vfs_write+0x33/0x190 ? handle_mm_fault+0x115/0x230 ? _cond_resched+0x16/0x40 vfs_write+0xb0/0x190 ksys_write+0x52/0xc0 do_syscall_64+0x5a/0x160 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f363e16ab50 Code: 73 01 c3 48 8b 0d 38 83 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 79 db 2c 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e e3 01 00 48 89 04 24 RSP: 002b:00007fff9a4c6378 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000009 RCX: 00007f363e16ab50 RDX: 0000000000000009 RSI: 000055c1cacc8e10 RDI: 0000000000000001 RBP: 000055c1cacc8e10 R08: 00007f363e435740 R09: 00007f363ea64700 R10: 0000000000000073 R11: 0000000000000246 R12: 0000000000000009 R13: 0000000000000001 R14: 00007f363e4345e0 R15: 00007f363e4303c0 Modules linked in: ip6table_filter ip6_tables snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic snd_hda_intel snd_hda_codec snd_hwdep snd_hda_core snd_seq snd_seq_device i915 snd_pcm snd_timer i2c_i801 snd soundcore i2c_algo_bit drm_kms_helper 86_pkg_temp_thermal video kvm_intel kvm irqbypass wmi e1000e ---[ end trace d301afa879ddfa25 ]--- The cause is because the register_snapshot_trigger() call failed to allocate the snapshot buffer, and then called unregister_trigger() which freed the data that was passed to it. Then on return to the function that called register_snapshot_trigger(), as it sees it failed to register, it frees the trigger_data again and causes a double free. By calling event_trigger_init() on the trigger_data (which only ups the reference counter for it), and then event_trigger_free() afterward, the trigger_data would not get freed by the registering trigger function as it would only up and lower the ref count for it. If the register trigger function fails, then the event_trigger_free() called after it will free the trigger data normally. Link: http://lkml.kernel.org/r/20180724191331.738eb819@gandalf.local.home Cc: stable@vger.kerne.org Fixes: 93e31ffbf417 ("tracing: Add 'snapshot' event trigger command") Reported-by: Masami Hiramatsu Reviewed-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Greg Kroah-Hartman

tracing: Fix missing return symbol in function_graph output

2018-07-11T14:26:43Z

commit 1fe4293f4b8de75824935f8d8e9a99c7fc6873da upstream. The function_graph tracer does not show the interrupt return marker for the leaf entry. On leaf entries, we see an unbalanced interrupt marker (the interrupt was entered, but nevern left). Before: 1) | SyS_write() { 1) | __fdget_pos() { 1) 0.061 us | __fget_light(); 1) 0.289 us | } 1) | vfs_write() { 1) 0.049 us | rw_verify_area(); 1) + 15.424 us | __vfs_write(); 1) ==========> | 1) 6.003 us | smp_apic_timer_interrupt(); 1) 0.055 us | __fsnotify_parent(); 1) 0.073 us | fsnotify(); 1) + 23.665 us | } 1) + 24.501 us | } After: 0) | SyS_write() { 0) | __fdget_pos() { 0) 0.052 us | __fget_light(); 0) 0.328 us | } 0) | vfs_write() { 0) 0.057 us | rw_verify_area(); 0) | __vfs_write() { 0) ==========> | 0) 8.548 us | smp_apic_timer_interrupt(); 0) <========== | 0) + 36.507 us | } /* __vfs_write */ 0) 0.049 us | __fsnotify_parent(); 0) 0.066 us | fsnotify(); 0) + 50.064 us | } 0) + 50.952 us | } Link: http://lkml.kernel.org/r/1517413729-20411-1-git-send-email-changbin.du@intel.com Cc: stable@vger.kernel.org Fixes: f8b755ac8e0cc ("tracing/function-graph-tracer: Output arrows signal on hardirq call/return") Signed-off-by: Changbin Du Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Greg Kroah-Hartman

tracing: Fix crash when freeing instances with event triggers

2018-06-06T14:44:33Z

commit 86b389ff22bd6ad8fd3cb98e41cd271886c6d023 upstream. If a instance has an event trigger enabled when it is freed, it could cause an access of free memory. Here's the case that crashes: # cd /sys/kernel/tracing # mkdir instances/foo # echo snapshot > instances/foo/events/initcall/initcall_start/trigger # rmdir instances/foo Would produce: general protection fault: 0000 [#1] PREEMPT SMP PTI Modules linked in: tun bridge ... CPU: 5 PID: 6203 Comm: rmdir Tainted: G W 4.17.0-rc4-test+ #933 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016 RIP: 0010:clear_event_triggers+0x3b/0x70 RSP: 0018:ffffc90003783de0 EFLAGS: 00010286 RAX: 0000000000000000 RBX: 6b6b6b6b6b6b6b2b RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8800c7130ba0 RBP: ffffc90003783e00 R08: ffff8801131993f8 R09: 0000000100230016 R10: ffffc90003783d80 R11: 0000000000000000 R12: ffff8800c7130ba0 R13: ffff8800c7130bd8 R14: ffff8800cc093768 R15: 00000000ffffff9c FS: 00007f6f4aa86700(0000) GS:ffff88011eb40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6f4a5aed60 CR3: 00000000cd552001 CR4: 00000000001606e0 Call Trace: event_trace_del_tracer+0x2a/0xc5 instance_rmdir+0x15c/0x200 tracefs_syscall_rmdir+0x52/0x90 vfs_rmdir+0xdb/0x160 do_rmdir+0x16d/0x1c0 __x64_sys_rmdir+0x17/0x20 do_syscall_64+0x55/0x1a0 entry_SYSCALL_64_after_hwframe+0x49/0xbe This was due to the call the clears out the triggers when an instance is being deleted not removing the trigger from the link list. Cc: stable@vger.kernel.org Fixes: 85f2b08268c01 ("tracing: Add basic event trigger framework") Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Greg Kroah-Hartman

tracing/uprobe_event: Fix strncpy corner case

2018-05-16T08:08:44Z

commit 50268a3d266ecfdd6c5873d62b2758d9732fc598 upstream. Fix string fetch function to terminate with NUL. It is OK to drop the rest of string. Signed-off-by: Masami Hiramatsu Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Song Liu Cc: Thomas Gleixner Cc: security@kernel.org Cc: 范龙飞 Fixes: 5baaa59ef09e ("tracing/probes: Implement 'memory' fetch method for uprobes") Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

tracing: Fix regex_match_front() to not over compare the test string

2018-05-16T08:08:43Z

commit dc432c3d7f9bceb3de6f5b44fb9c657c9810ed6d upstream. The regex match function regex_match_front() in the tracing filter logic, was fixed to test just the pattern length from testing the entire test string. That is, it went from strncmp(str, r->pattern, len) to strcmp(str, r->pattern, r->len). The issue is that str is not guaranteed to be nul terminated, and if r->len is greater than the length of str, it can access more memory than is allocated. The solution is to add a simple test if (len < r->len) return 0. Cc: stable@vger.kernel.org Fixes: 285caad415f45 ("tracing/filters: Fix MATCH_FRONT_ONLY filter matching") Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Greg Kroah-Hartman

tracing: probeevent: Fix to support minus offset from symbol

2018-03-28T16:39:23Z

commit c5d343b6b7badd1f5fe0873eff2e8d63a193e732 upstream. In Documentation/trace/kprobetrace.txt, it says @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) However, the parser doesn't parse minus offset correctly, since commit 2fba0c8867af ("tracing/kprobes: Fix probe offset to be unsigned") drops minus ("-") offset support for kprobe probe address usage. This fixes the traceprobe_split_symbol_offset() to parse minus offset again with checking the offset range, and add a minus offset check in kprobe probe address usage. Link: http://lkml.kernel.org/r/152129028983.31874.13419301530285775521.stgit@devbox Cc: Ingo Molnar Cc: Tom Zanussi Cc: Arnaldo Carvalho de Melo Cc: Ravi Bangoria Cc: stable@vger.kernel.org Fixes: 2fba0c8867af ("tracing/kprobes: Fix probe offset to be unsigned") Acked-by: Namhyung Kim Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Greg Kroah-Hartman